Split flap display module

ABSTRACT

In the present split flap display system each vane carries a code configuration representing the corresponding character. Code reading mechanism is provided for reading the code configuration from each vane as it comes into display position and comparing it with a code configuration that has been generated or selected to represent the desired character. When those two codes agree, the drive is terminated with the selected vane in display position. A preferred type of code is binary four out of eight, and is applied to the vanes by selectively notching the vane edge at locations corresponding to the respective digits. Code reading switches can then be operated mechanically by the positioned vanes. Each vane in display position is urged toward switch operating position by abutment means acting between the vane and the vane carrier. When in display position, each vane is locked against reverse rotation of the carrier.

Lagasse et al.

[ NOV. 13, 1973 Assignee:

Filed:

SPLIT FLAP DISPLAY MODULE Inventors: Eugene F. Lagasse, Chester; Francis X. Geissler, Westbrook, both of Conn.

Conrac Corporation, New York,

May 15, 1972 Appl. No.: 253,014

US. Cl 40/35, 40/52 R, 40/68.4,

Int. Cl. G09f 11/06 Field of Search 40/33, 35, 68.4,

40/68.6, 73.4, 104.1, 104.2, 104.3, 104.09, 53 R, 72, 28 R, 52 R; 209/80.5, 110; 340/149, 324 R, 324 AD, 339, 325, 378 R References Cited UNITED STATES PATENTS Primary Examiner-Robert w. Michell Assistant Examiner-Vance Y. Hum Att0rneyCharlton M. Lewis [57] ABSTRACT In the present split flap display system each vane carries a code configuration representing the corresponding character. Code reading mechanism is provided for reading the code configuration from each vane as it comes into display position and comparing it with a code configuration that has been generated or selected to represent the desired character. When those two codes agree, the drive is terminated with the selected vane in display position. A preferred type of code is binary four out of eight, and is applied to the vanes by selectively notching the vane edge at locations corresponding to the respective digits. Code reading switches can then be operated mechanically by the positioned vanes. Each vane in display position is urged toward switch operating position by abutment means acting between the vane and the vane carrier. When in display position, each vane is locked against reverse rotation of the carrier.

5 Claims, 11 Drawing Figures PHENTEDHUY 13 1975 SHEET 10F 3 FATENTEUHUY 13 I975 3,771; 242

SHEET 2 CF 3 PATENTEDHDV 13 1975 SHEET 3 BF 3 SPLIT FLAP DISPLAY MODULE This invention concerns selective display devices of the type known as split flap displays, in which display cards or vanes are pivotally mounted on a rotatable carrier. During each display the front face of one vane is shown in the upper half of the display window while the back face of the preceding vane is shown in the lower half of the window. As carrier rotation releases the edge of the upper vane, it flips down, covering the lower half of the previous display and uncovering the next following vane in the upper half of the display.

The prior art includes numerous mechanisms for operating such displays, either for stepping through a series of displays in predetermined order or for presenting any desired display on command, usually with provision for remote control.

To provide capability for selectively displaying a wide variety of different messages, it is preferred to employ a distinct rotatable unit for selecting and displaying each alphanumeric character of the desired message. Such units must be mounted close together to permit normal spacing of the letters making up a word. One object of the present invention is to provide selection and control mechanism which is extremely compact axially of the rotating shafts.

A further object of the invention is to insure accurate response to the selection process, without any possibility of error due to backlash of drive gears or errors of phase adjustment between the vane carrier and a separately journaled control member.

The invention further provides remarkably simple means for positively preventing reverse rotation of the vane carrier once it has been stopped in the selected position. By effectively locking the carrier against such reverse rotation, it is possible to maintain the upper vane of 'each display firmly pressed forward into the 7 plane of the display window. That has the advantage of insuring uniform alignment of adjacent characters of a display, and is also utilized to advantage by the particular preferred selection system of the invention.

Those and other objects and advantages of the invention are attained in part by driving the rotation of the vane carrier under control of code configurations that are carried directly by the display vanes themselves. Code reading mechanism is provided for reading the code from each vane as it comes into display position with its upper edge at the upper frame of the display window. In accordance with the invention, whenever the code corresponding to the desired character is detected on the vane in display position the carrier drive is terminated and the carrier stops.

Since each code configuration is directly carried by the vane to which it corresponds, play in the drive train is immaterial. By positioning the code adjacent the radially outer vane edge, the code reading mechanism can conveniently be positioned above the display window, and several display units can be mounted in a row directly adjacent each other.

A preferred type of code for use in the present display units is of the type known as select codes, of which binary four out of eight codes are typical. In the latter codes, for example, out of the eight code digits, just four have the value 1 and four have the value in every code configuration that is used. A known advantage of select codes is the relative simplicity of the logical circuitry by which two code configurations can be compared and a signal generated if they are identical. The

recent US. Pat. No. 3,501,761 to Capellari shows a select code for controlling a split flap display in which each display evidently includes a complete message rather than a single character. Capellari requires a separate control drum on which all code configurations are formed.

In applying select code configurations directly to the individual display vanes, the present invention may employ many different code structures and reading procedures. The code can, for example, consist of respective light and dark areas printed on the front face of each vane adjacent the radially outer edge, and can be read optically by providing a suitable light source for illuminating the code area. Light from the code areas of the separate digits is then detected by respective photoresponsive elements which produce electrical output signals in response to the value of each code digit. After conventional amplification, such signals can operate respective electronic or electromechanical switches, which can readily be connected in analagous manner to the code reading switches to be described.

A presently preferred form of code comprises presence or absence of recesses or notches formd in the vane edge at definite respective locations corresponding to the several code digits. Particularly when employed in combination with the vane locating structures to be described, such mechanically encoded information can be read effectively by switches directly operated by resilient switch arms that are actuated mechanically by contact with those portions of the code area that are not notched. One contact of each switch can be on the vane, if desired, if the vanes are formed of electrically conductive material, or if conductive areas are used on the vanes in forming the code.

A full understanding of the invention, and of its further objects and advantages, will be had from the following description of an illustrative manner of carrying it out. That description is to be read with reference to the accompanying drawings, in which:

FIG. 1 is a front elevation of an illustrative display unit in accordance with the invention;

FIG. 2 is a section on line 2-2 of FIG. 1;

FIG. 3 is a section on line 3-3 of FIG. 2, at enlarged scale;

FIG. 4 is a section on line 4-4 of FIG. 3, at enlarged scale;

FIG. 5 is a schematic perspective, partly broken away, representing the control assembly of the unit of FIG. 1;

FIG. 6 is a section generally on line 6-6 of FIG. 5;

FIG. 7 is a section on line 7-7 of FIG. 6;

FIG. 8 is a section on line 8-8 of FIG. 6;

FIG. 9 corresponds to a portion of FIG. 6 at further enlarged scale;

FIG. 10 is a schematic diagram representing electrical connections to a remote code generating station; and

FIG. 11 is a schematic perspective representing a code generator.

The split flap display unit of the present invention, as shown illustratively in the drawings, comprises the frame structure 10, the vane carrier 30, which is journaled on frame 10 on the axis 31 and pivotally carries a circular array of display vanes 40, the motor 50 for driving carrier 30, and the control assembly 60 for controlling the motor operation.

Frame comprises the two generally rectangular side plates 12 and 13, which are rigidly held in spaced parallel relation by the three struts 14, 15 and 16 and by control assembly 60. The struts are preferably fixedly mounted on one plate and secured to the other plate by screws 17, accurately defining the plate separation. Control assembly 60 is rigidly secured to both plates by the screws 61, and is accurately located by the dimples 62, which are formed on the inner plate faces and enter fitting recesses in the assembly.

A plurality of display units are typically mounted in side by side relation on a horizontal supporting shelf, shown in fragmentary form at 22. The horizontal bottom edges of frame plate 12 and 13 are inwardly flanged at 24, and track structures 26 are disposed on shelf 22 along which each display device may-be slid forward into position and retained by the screws 27. Each frame 10 is open at the front, forming a display window 20. That window is typically framed on the sides by the plastic strips 18, riveted to the respective frame plates, on the bottom by the strip 23 carried by the front edge of shelf 22, and on the top by the front face of control assembly 60.

Vane carrier 30 comprises a shaft 32 which rigidly carries the spaced parallel disks 34 and the driving gear 36. Shaft 32 is journaled in the bushings 33, which are set into the respective frame plates 12 and 13 and define the carrier axis 31. The display vanes 40 are mounted between disks 34 for free but limited swinging movement about respective vane axes 41 which are parallel to each other and to the carrier axis. Each vane axis is approximately defined by a pair of holes 38 formed directly opposite each other in the respective disks, the holes in each disk forming a coaxial circular array. Those holes freely receive the ears 42, which project laterally from the vanes adjacent their inner edges, as shown best in FIG. 3. Each hole 38 is preferably of general D-shape, positioned symmetrically with respect to the carrier axis with the straight side of the D toward that axis (FIG. 4).

Each vane 40 is essentially rectangular in shape with an axial width slightly greater, over most of the vane length, than the spacing between the outer faces of disks 34. Ears 34 are formed mainly by cutting notches 44 in the vane side edges outward of the ears. Notches 44 are just deep enough to provide ample clearance for disks 34, and extend radially outward from the ears a uniform distance to the square limiting edges 46 (FIG. 3). Those notch edges form abutments which limit the swinging movement of the vanes about the respective vane axes 41 in both directions by striking the disk peripheries 35. The radial notch dimension is selected to arrest swinging of each vane in a plane just short of perpendicular to the plane through the vane and carrier axes, as more fully described below. Carrier axis 31 is so located on frame 10 that disks 34 are approximately tangent to the vertical forward edges of frame plates 12 and 13 near the horizontal center line of window 20.

Carrier 30 is driven about axis 31 in the forward direction, counterclockwise as seenin FIG.. 2, by motor 50, which is typically mounted on frame plate 12 by the posts 52. Motor 50 preferably incorporates within its housing a speed reduction gear train terminating in the output pinion 56. That drive pinion is typically coupled to carrier gear 36 via the single idler gear 54,journaled freely on frame plate 12. Although the illustrated type of rotary motor is preferred, a stepping motor may be employed if desired.

Carrier rotation brings the display vanes 40 successively into the position shown at 40a in FIG. 2 with the radially otiter vane edge retained by the upper frame of window 20 and the forward vane face visible in the upper half of the window. Further carrier rotation disengages the vane edge, allowing vane 40a to flip downward about its axis 41 to the position 40b. The back face of the vane is then visible in the lower half of the window, where it is held in the proper plane by the pileup of vanes against the suitably located stud 14. At the same time the next following vane presents its forward face in the upper half of the window. Thus, each display comprises the front face of one vane and the rear face of the preceding vane, and the total number of available displays equals the number of vanes. For convenience of description, and for further reasons which will become more clear, each display will be considered to be associated with the vane that carries its upper half.

In accordance with an important aspect of the present invention, motor operation for bringing a selected display into window 20 is controlled by means of code configurations carried by the vanes themselves. As shown illustratively in the present embodiment, the code comprises eight binary code bits arranged in line along the vane edge and forming a four out of eight code. That is, on each vane four of the bits have the value 0 and the other four the value 1. A linear array of code reading transducers is mounted just above window 20 in position to respond to the respective code bits on the particular vane that is in or close to position 40a. A wide variety of types of code markings and corresponding transducer structures may be employed. The present illustrative code represents digits of value 0 by the notches 48 formed selectively in the outer vane edge at specific positions for the respective code digits, leaving unnotched areas 49 for value 1. Those digit positions are arranged in two groups of eight each, typical positions being indicated by the lines A through H in FIGS. 1 and 5. Thus, the specific code configuration for the vane carrying the letter Y is shown illustratively as 01011010.

The present code reading transducers comprise switches mounted inward of the vertical wall 64 of the angle frame 62, which is the main structural member of control assembly 60. The generally rectangular switch board is spaced from wall 64 by the spacer block 72. That block is molded or machined to provide on its inner face the accurately formed upper and lower mounting surfaces 74 and 76 for supporting the switch board, and the abutment surfaces 90 and 92 for defining the position of a vane edge as it reaches display position. Upper mounting surface 74 typically extends the full horizontal dimension of switch board 70. The lower portion of the board is supported on three separate support surfaces 76, formed on respective mutually spaced bosses 78. Block 72 is recessed between and above those bosses to form the switch chamber 77. Eight independently movable switch arms 80 are formed as a unitary comb-like element 82 by deeply notching a sheet of resilient metal (FIG. 7). The comb back is rigidly clamped by the rivets 71 between upper mounting surface 74 of block 72 and switch board 70, and may be spaced from the latter by the spacer 83. The switch arms 80 extend downward in chamber 76 in spaced relation to the switch board. The switch arms 80 are arranged in two groups of four arms each, the groups being accommodated on opposite sides of the central support boss 78.

Movable switch contacts 84 are mounted on the respective switch arms 80 near their free ends and facing board 70. Electrical connection is made in parallel to all those contacts through the terminal tab 85. The fixed switch contacts 86 are mounted on switch board 70, typically by printed circuit techniques, together with the connections 87 between those contacts and the respective terminals 88. The flexible lead wires 89 pass through holes in the board and are soldered to the respective terminals 88.

The lower portions of the three bosses 78 that carry support surfaces 75 project beyond the plane of the circuit board and form the first and second abutment surfaces 90 and 92, with the sharp steps 93 between them. As each vane approaches display position, its front surface first lightly engages the three surfaces 90, as indicated for vane 40c in FIG. 9. If the carrier continues to turn, pulling vane 40c downward, the vane edge slips off surfaces 90 at the steps 93 to the position 40a defined by the three-lower surfaces 92. The free end of each switch arm 80 is bent inward in spaced relation below the lower edge of switch board 70, and is then preferably curled down to form a smooth vane engaging formation 94. The switch arms are prestressed to normally-hold their contacts 84 and 86 closed under light pressure. In that normal position of the switch arms each formation 94 is so placed that it comfortably clears a vane in approach position 400. However, when the vane reaches display position 40a, a switch arm at an unnotched position of the vane is deflected, opening the switch, as at 80a in FIG. 9. Only those switches opposite code notches in vane 40a remain closed. Extreme deflection of switch arms 80, as during assembly, is prevented by the ledge 96. The use of normally closed switches insures drive of the vane carrier even though one or more vanes are missing.

For remotely controlled operation of the described display unit, connection is typically made to the unit via the nine wire cable 100, the connector 102 and the circuit board 104, which is rigidly mounted on the upper wall 66 of angle frame 62.-Circuit board 104 carries the eight code connector contacts 106 and the common contact 108. Code contacts 106 are connected via the printed circuit strips 110 to the respective wires 89, already described, and thence to the eight respective fixed switch contacts 86 in definite order. Common contact 108 is similarly connected to a circuit including in series the wire 114, motor 50 and the wire 116, which is connected in parallel to all eight movable switch contacts 84.

At the remote control station, cable 100 is connected to the power source 118 to the code generator 120, which may be of conventional construction. As shown schematically in FIG. 10, the code generator comprises the metal base plate 122 and the array of movable switch contacts 124, typically eight in number, which are spring biased to normally engage plate 122. The common line in cable 100 is connected via power source 118 to plate 122. The code wires of cable 100 are connected to the respective switch contacts 124 in proper order. A code command signal can then be generated at station 120 by inserting between plate 122 and switch contacts 124 a card 126 of insulative material which has been pre-punched to provide holes at the switch positions corresponding to the complement of the code on the desired vane. With such a card in position power source 118 is connected through code generator 120 to four selected switches in the display unit. Motor 50 will then be driven until the vane in display position opens all four of those switches. A single command card 126, typically a conventional IBM" card, can carry up to rows of holes for developing 80 corresponding code configurations for the simultaneous control of the same number of display units, all typically identical in construction. Selection of the desired message is then accomplished by merely selecting the proper command card and inserting it in a suitable code generator (FIG. 11).

As already indicated in connection with FIG. 3, the present structure for mounting the display vanes on carrier 30 includes structure for positively limiting their swinging movement about vane axes 41. That structure typically comprises the accurate dimensioning of vane notches 44 so that the outer notch end 46 engages the periphery 35 of carrier disk 34 at the desired limiting vane angle. That angle is selected so that a vane in display position 40a is slightly bowed outward. The resilient stiffness of the vane then produces an outward force on the outer edge portion of the vane causing it to firmly engage defining surface 92. That action has several useful results. It insures ample force for operating the code reading switches. It also insures rapid flipping action of each vane as it is released from ledge 92 by continuing drive of vane carrier 30. Also, the described slight bowing of vane 40a exerts a reverse couple upon carrier 30, reducing any tendency for the motor and carrier to coast after deletion of power in response to detection of the desired vane in display position. Further braking of the motor can be produced, if desired, as by providing a magnetic brake that is applied in known manner through relay operation whenever power to the motor is interrupted. Sufficiently rapid braking can ordinarily be obtained by connecting in shunt to the motor a resistance of suitable value to produce effective braking without significantly reducing the motor power. Such a resistance is indicated schematically at 130 in FIGS. 3, 6 and 10.

After the vane carrier has stopped at display position for the selected vane, the described bowing of the vane continues to exert a reverse torque on the carrier. However, significant reverse movement is prevented by the horizontal surfaces 93, which form steps between the previously described abutment surfaces and 92. Those steps are in the path of the vane edge, positively preventing its reverse displacement. Provision of the sharp steps 93 between abutment surfaces 90 and 92 also assists positive and prompt switch operation as each vane moves toward display position. After the vane edge leaves surface 90 it is sharply accelerated toward surface 92, and therefore strikes the switch arms with a flipping action that adds the force of inertia to that due to the resilient bowing of the vane. The lower edge of second abutment surface 92 is preferably located at such distance from step 93 that the vanes 40c and 40a engaging the first and second abutment surfaces become released from those surfaces substantially simultaneously.

We claim:

1. Selectively controllable display apparatus including a carrier journaled on a carrier axis, a plurality of resilientlyflexible display vanes pivotally mounted on the carrier on respective vane axes parallel to the carrier axis and angularly spaced thereabout, selectively e'nergizable driving means for the carrier, and abutment means for defining the plane of the outer edge portion of each vane as it approaches a predetermined display position, said apparatus further comprising digital code configuration means for representing a plurality of digits of a digital code for identifying the displays associated with the respective vanes, said code means comprising selectively recessed areas on the radially outer edge portions of the respective vanes,

code sensing means comprising an electrical switch for each code digit and switch operating means adjacent the abutment means, said switch operating means being selectively engageable by said recessed areas as each vane approaches display position for selectively operating the respective switches,

interengageable means on the carrier and on the respective vanes for positively limiting the pivotal movement of the radially inner portion of each vane relative to the carrier at such mutual angle that each vane upon approaching display position is resiliently deflected to press said vane areas into firm engagement with the switch operating means and thereby insure effective switch operation,

code selection means for developing electrical signals representing a selected one of said code configura- 30 tion means,

and control means for normally energizing the driving means and for automatically disabling the driving means under joint control of the sensing means and said electrical signals when the sensed code configuration corresponds to said electrical signals.

2. Apparatus according to claim 1 in which said switch operating means comprise spring means prestressed to normally hold the respective switches closed and including fingers in position to be selectively engaged by the respective said recessed areas as each vane approaches said display position, such engagement deflecting the finger against the force of said spring means and thereby opening the associated switch.

3. Apparatus according to claim 1 in which said abutment means comprise first and second surfaces in position to successively engage the forward vane face adjacent the outer vane edge as each vane approaches said display position, the surfaces lying in mutually spaced planes and being separated by a step at which the vane edge is abruptly released in passing from the first to the second surface, and said switch operating means are engageable by said recessed areas only after the vane edge has been released at the step.

4. Apparatus according to claim 3 in which said switch operating means comprise spring means prestressed to normally hold the respective switches closed and fingers in position to be selectively engaged by the respective said recessed areas after the vane edge has been released at the step, slich engagement deflecting the finger against the force of said spring means and thereby opening the associated switch.

5. Apparatus according to claim 1 including a rigid step formation associated with said abutment means in position to directly oppose the radially outer edge of a vane in said display position and thereby prevent reverse'rotation of the carrier despite vane deflection. 

1. Selectively controllable display apparatus including a carrier journaled on a carrier axis, a plurality of resiliently flexible display vanes pivotally mounted on the carrier on respective vane axes parallel to the carrier axis and angularly spaced thereabout, selectively energizable driving means for the carrier, and abutment means for defining the plane of the outer edge portion of each vane as it approaches a predetermined display position, said apparatus further comprising digital code configuration means for representing a plurality of digits of a digital code for identifying the displays associated with the respective vanes, said code means comprising selectively recessed areas on the radially outer edge portions of the respective vanes, code sensing means comprising an electrical switch for each code digit and switch operating means adjacent the abutment means, said switch operating means being selectively engageable by said recessed areas as each vane approaches display position for selectively operating the respective switches, interengageable means on the carrier and on the respective vanes for positively limiting the pivotal movement of the radially inner portion of each vane relative to the carrier at such mutual angle that each vane upon approaching display position is resiliently deflected to press said vane areas into firm engagement with the switch operating means and thereby insure effective switch operation, code selection means for developing electrical signals representing a selected one of said code configuration means, and control means for normally energizing the driving means and for automatically disabling the driving means under joint control of the sensing means and said electrical signals when the sensed code configuration corresponds to said electrical signals.
 2. Apparatus according to claim 1 in which said switch operating means comprise spring means prestressed to normally hold the respective switches closed and including fingers in position to be selectively engaged by the respective said recessed areas as each vane approaches said display position, such engagement deflecting the finger against the force of said spring means and thereby opening the associated switch.
 3. Apparatus according to claim 1 in which said abutment means comprise first and second surfaces in position to successively engage the forward vane face adjacent the outer vane edge as each vane approaches said display position, the surfaces lying in mutually spaced planes and being separated by a step at which the vane edge is abruptly released in passing from the first to the second surface, and said switch operating means are engageable by said recessed areas only after the vane edge has been released at the step.
 4. Apparatus according to claim 3 in which said switch operating means comprise spring means prestressed to normally hold the respective switches closed and fingers in position to be selectively engaged by the respective said recessed areas after the vane edge has been released at the step, such engagement deflecting the finger against the force of said spring means and thereby opening the associated switch.
 5. Apparatus according to claim 1 including a rigid step formation associated with said abutment means in position to directly oppose the radially outer edge of a vane in said display position and thereby prevent reverse rotation of the carrier despite vane deflection. 